Bryan Johnstone (bryan0johnstone)

1 answer · asked · Lesson: Everything is a Bouncing Ball · Course: Blender Animation Bootcamp

Using Math to find Increasing Speed

So the increase in spacing is just a basic  Velocity Formula, right?
In truth I'm sure the Graph Editor will handle the bulk, but knowing the equation could help if I need to brute force a problem, or figure it out on paper.

  • crew

    Hi Bryan,

    I like your thinking, although I doubt you would find it easier to figure out on paper.  I know I don't find it easier!

    Here's the equation...
    (sqrt(h*g/2)*2)*((frame/fps)%((sqrt(h*g/2)*2)*2/g)) - (g*((frame/fps)%((sqrt(h*g/2)*2)*2/g))**2)/2

    Where:

    v = velocity at the ground

    g = acceleration of gravity

    t = (frame/fps)%(v*2/g)

    fps = scene's frame rate

    frame = current frame


    That will get the graph editor to do the bulk of the work, but then the only way to tweak it would be to edit your variables (like gravity).

    But you often are working in a scene that doesn't have real world scale plus you wouldn't be able to stylise your timing and spacing to make it better than real life.

    You might want to emphasise the weight or the hangtime for a different effect.


    So in summary, it's much much easier to control your timing and spacing ;)


    (This comes from a person who has tried this haha)